In The Case of The Murders Around Alchemy.

This time is an investigation about Alchemy by Theseus.

The characters in this case arrived at the
island renkin on which they are each housed in one of the rooms of the 2nd
floor of one building of this land. But the plan of this story is very original
and recalls something Hajime. It was only the third episode of the
investigation that Kindaichi will remember seeing something that reminded him
of it in the library of his grandfather and find the same kind of symbol in a
book he found the building where it is located (10 minutes after the beginning
of episode 8 of Kindaichi return in the first season). (file a)

This is one of 8 figures that appear in
the alchemy book Sylva philosophorum and
written by Cornelius Petraeus in the seventeenth century. This symbol represents
the development of the philosopher's stone. Here is the translation of what is
written in Latin on this scheme. On the outer circle is written : sed omnibus paucis luceo, ie "for
all and yet for some I light" (ie motto). Then the 4 elements are each represented
on a square angle : ignis : fire, aer : air, terra : earth and aqua :
water. On the octagon are inscribed the qualities of the four elements listed
above : calidus, hot, humidus (male) or humida (female), wet, frigida,
cold, siccus (male) or sicca, or dry hair. The relationship
between the fire and the air is described as activated, active and that between
the earth and water as passiva passive. Fire and earth are said sulphurea : sulfuric.
As the air and water are said mercurialia : mercurial. There is also a triangle
with an inscription in each corner : sol,
sun, luna, moon and azoth, an alchemical term for "raw
material". Then we read on the lines of the triangle non est : it is not. While the lines that join the center of the
image is written est : it is. Finally, there remains that what is central : lapis philosophorum, the stone of the
philosophers.